The invention relates to a hydraulic drive device comprising a piston which is displaceably guided in a cylinder chamber along a working axis, and which defines a working pressure chamber which may be pressurized by hydraulic fluid, and comprising a control means guided in the piston at least partially between various control states, for controlling the throughflow of hydraulic fluid from a high pressure supply into the working pressure chamber to move the piston in the working direction, and from the working pressure chamber to a return flow chamber. The invention further relates to a method for operating a hydraulic drive device comprising a piston which is displaceably guided in a cylinder chamber and which defines a working pressure chamber, the working pressure chamber being pressurized by hydraulic fluid to move the piston in the working direction.
Hydraulic drive devices and methods of the aforementioned type are known in various embodiments. In this respect, reference is made to the prior art, for example, to EP 0 296 104 B1. A common feature in the prior art is that retraction and extension movements of the piston are effected by means of hydraulic fluid from a high pressure supply. Such devices are used, in particular, in stamping, punching, nibbling, bending or forming machines. In this typically highly dynamic operation, naturally the volumetric flow of hydraulic fluid from the high pressure supply is high, and sufficient energy has to be provided.
Further hydraulic drives have been disclosed in DE 37 20 266 C2 and EP 0 296 104 B1.